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The band alignment of p-Cu2O/n-AlxGa1–xN heterojunction with x up to 0.15 was studied by X-ray photoelectron spectroscopy. The conduction band offset between binary Cu2O and ternary AlxGa1–xN is found to decrease with increasing x. The data suggest that a flatband situation in the conduction band of p-Cu2O/n-AlxGa1–xN heterojunctions can be achieved for x about 0.4, which is an Al-content where n-type doping is still feasible. Thus, n-AlxGa1–xN with x between 0.4 and 0.6 may be a suitable window material for heterojunction solar cells with a p-Cu2O absorber layer. The current-voltage characteristics of the p-Cu2O/n-AlxGa1–xN heterojunctions under illumination confirm the anticipated improvement of the photovoltaic properties with increasing x. [ABSTRACT FROM AUTHOR]

Polycrystalline Cu2O thin films were prepared on c-sapphire substrates by reactive radio-frequency sputtering at various temperatures between 500 and 925K employing a metallic target and utilizing an argon/hydrogen/oxygen gas mixture. It is demonstrated that the use of hydrogen in the sputter deposition process beneficially affects the transport properties of the Cu2O films obtained. Correlating the amount of hydrogen incorporated into the thin films, the film morphology and the transport and luminescence properties demonstrate that in this approach hydrogen is predominantly accumulated at the grain boundaries of the polycrystalline films, leading to a lower film resistivity due to the reduction of grain boundary scattering. It is demonstrated that a suitable employment of hydrogen in the growth process of Cu2O material for solar cell applications improves the material properties significantly. [ABSTRACT FROM AUTHOR]

Brain metastases are major complications of common cancers. Tumor type and proneness to the CNS are thought to define the number and size of brain metastases. It is not known if intrinsic vascular factors can also have an effect. Restricted perfusion due to cerebral small vessel disease is frequent in elderly patients and causes white matter lesions (WML). The aim of this analysis was to evaluate a possible negative effect of WML and patient age on the number and size of brain metastases (BM) of different tumor entities. Pre-therapeutic 3 T brain magnetic resonance imaging (MRI) of 200 patients with BM were analyzed. Location, size and number of BM (NoM) were determined. T2 hyperintensive WML were scored according to Fazekas-Score (grade I-III). Patients with WML grade 1 (NoM: 5.59; p = 0.009) and grade 2 (NoM: 3.68; p = 0.002) had significantly less BM than patients without WML (NoM: 6.99). This effect was present in subgroups of different tumors: NSCLC (p = 0.05), other tumors than NSCLC (p = 0.048). Age (≤65 or >65 years) was positively correlated with the degree of WML but not with number (pNoM = 0.832) or mean diameter (pmDM = 0.662) of brain metastases. While patient age did not appear to be relevant, increasing WML were associated with lower number of brain metastases in different tumor types. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the prevalence of lung cancer in a high-risk asbestos-exposed cohort using low-dose MDCT. Of a population of 5,389 former power-plant workers, 316 were characterized as individuals at highest risk for lung cancer according to a lung-cancer risk model including age, asbestos exposure and smoking habits. Of these 316, 187 (mean age: 66.6 years) individuals were included in a prospective trial. Mean asbestos exposure time was 29.65 years and 89% were smokers. Screening was performed on a 16-slice MDCT (Siemens) with low-dose technique (10/20 mAs(eff.); 1 mm/0.5 mm increment). In addition to soft copy PACS reading analysis on a workstation with a dedicated lung analysis software (LungCARE; Siemens) was performed. One strongly suspicious mass and eight cases of histologically proven lung cancer were found plus 491 additional pulmonary nodules (average volume: 40.72 ml, average diameter 4.62 mm). Asbestos-related changes (pleural plaques, fibrosis) were visible in 80 individuals. Lung cancer screening in this high-risk cohort showed a prevalence of lung cancer of 4.28% (8/187) at baseline screening with an additional large number of indeterminate pulmonary nodules. Low-dose MDCT proved to be feasible in this highly selected population. [ABSTRACT FROM AUTHOR]

Objectives: To implement a novel voxel-based technique to identify statistically significant local cartilage deformation and analyze in-vivo topographic knee cartilage deformation patterns using a voxel-based thickness map approach for high-flexion postures. Methods: Sagittal 3T 3D-T1w-FLASH-WE-sequences of 10 healthy knees were acquired before and immediately after loading (kneeling/squatting/heel sitting/knee bends). After cartilage segmentation, 3D-reconstruction and 3D-registration, colour-coded deformation maps were generated by voxel-based subtraction of loaded from unloaded datasets to visualize cartilage thickness changes in all knee compartments. Results: Compression areas were found bifocal at the peripheral medial/caudolateral patella, both posterior femoral condyles and both anterior/central tibiae. Local cartilage thickening were found adjacent to the compression areas. Significant local strain ranged from +13 to -15 %. Changes were most pronounced after squatting, least after knee bends. Shape and location of deformation areas varied slightly with the loading paradigm, but followed a similar pattern consistent between different individuals. Conclusions: Voxel-based deformation maps identify individual in-vivo load-specific and posture-associated strain distribution in the articular cartilage. The data facilitate understanding individual knee loading properties and contribute to improve biomechanical 3 models. They lay a base to investigate the relationship between cartilage degeneration patterns in common osteoarthritis and areas at risk of cartilage wear due to mechanical loading in work-related activities. Key points: • 3D MRI helps differentiate true knee-cartilage deformation from random measurement error • 3D MRI maps depict in vivo topographic distribution of cartilage deformation after loading • 3D MRI maps depict in vivo intensity of cartilage deformation after loading • Locating cartilage contact areas might aid differentiating common and work-related osteoarthritis [ABSTRACT FROM AUTHOR]

Supratentorial white matter is an important part of the brain and a major site of detrimental effects after whole brain radiotherapy (WBRT). It is not known if prevalence of metastases in white matter justifies standard inclusion of white matter in whole brain treatment. In this retrospective analysis we examined the frequency of metastasis in supratentorial deep cerebral white matter with cerebral magnetic resonance imaging (MRI). Deep white matter (DWM) was defined as white matter in corpus callosum with forceps anterior and posterior and centrum semiovale. Lesions extending from grey matter, gyrus or ventricles into white matter were not classified as DWM metastases. Brain MRI of 198 patients from two centres were analyzed. In total 1330 metastases were counted and only 4.6 % were located in DWM. Metastases in DWM were small (median diameter 6 mm). Only 1/41 patients (2 %) with a singular metastasis had a DWM metastasis, 2/35 patients (6 %) with 2 metastases had a DWM metastasis, 14/79 patients (18 %) with 3-9 metastases and 12/43 patients (28 %) with >9 metastases had a single or more DWM metastases (p = 0.003). There appeared to be tumor related differences with renal cell carcinoma showing significantly more DWM metastasis (6/17, 35 %), than NSCLC (11/85, 13 %, p = 0.024), breast cancer (1/20, 5 %, p = 0.019) or colorectal cancer (0/10, 0 %, p = 0.033). Overall, relevant preservation of DWM from metastases, especially in oligometastatic disease, was shown. This implies that DWM in patients with only few brain metastases is unnecessarily damaged by conventional WBRT. [ABSTRACT FROM AUTHOR]

Objective: Worldwide demand has increased for the development of a computed tomography (CT) classification system that supplements the ILO classification of radiographs for pneumoconioses. The authors aimed to show preliminary reliability test results for selected referent films for the CT classification system developed through an international effort by researchers from seven countries. Methods: Reading trials by eight physicians who have considerable experience in pneumoconioses using a total of 114 lung zones consisting of 6 lung zones of 19 CT films of dust-exposed workers were performed to assess reliability of the classification system by weighted κ. The results were also utilized for selecting reference films. Results: A good agreement was observed for both first and second reading trials for rounded opacities (weighted κ=0.76, 0.74, first and second trial results, respectively), irregular opacities (0.60, 0.48), emphysema (0.56, 0.70) and honeycombing (0.72, 0.79). Ground glass opacities, on the other hand, showed moderate agreement (0.43, 0.38). Intra-reader agreements among eight readers were shown in the same table as the mean and standard deviation of weighted κ statistics. The inter-reader agreement for pleural thickening was not as good as for parenchymal lesions. Discussion: The CT classification development may pioneer noble and sensitive medical screening for dust-exposed workers in selected settings. This system may be applied to radiographic borderline cases of profusion 0/1 and 1/0 by the ILO classification, in a setting that assures the occupational safety and health of workers exposed to some newly developed chemical compounds. [ABSTRACT FROM AUTHOR]

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Copyright of Der Radiologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The standard ILO classification for pneumoconiotic changes using conventional X-ray films has become well established. In recent years computed tomography has played an increasing role in occupational medicine and above all in the assessment of pneumoconiosis. Therefore a standardised method of classification for CT also seems necessary. A system of classification developed by occupational hygienists and radiologists allows a detailed description of parenchymal and pleural changes and the use of 28 additional symbols. Furthermore, special diagnoses relevant to occupational medicine and additional comments can be made. The classification system was tested in practice in the research project 'Early diagnosis of asbestos-related diseases' ( Frühdiagnostik asbestverursachter Erkrankungen). It was shown to be both practicable and easily reproducible, intra-individually and interindividually. [ABSTRACT FROM AUTHOR]